A self-opening handle for a heavy duty artistic knife includes a handle which is combined with a pair of corresponding halves and rotatably connected on their rear ends, a blade rack slidably disposed in the front portion, a blade chamber formed in the rear portion and a swivel lock locking the lower middle portion thereof. The feature is that a magnet disposes in a lower inner wall of each of the corresponding halves with the identical pole toward each other so that when the swivel lock is at a unlocking position, the pair of corresponding halves will automatically open a large angle due to the expelling force of the magnets. Therefore providing a convenient and swift changing of the blade from the blade rack.